Error Message "Booting from hard disk... error: no such partition.

[randomuser1990]

I encountered this error while working with Proxmox and Ubuntu VM. Whenever I attempt to start my Ubuntu VM, I receive the following error message:

"Booting from hard disk...
error: no such partition.
Entering rescue mode...
grub rescue>"

This issue started occurring after I attempted to enlarge the disk drive for the VM by following the instructions provided in the Proxmox Wiki (https://pve.proxmox.com/wiki/Resize_disks).
I encountered a problem at the step where I executed the following command:

"parted /dev/sda
(parted)
print
Warning: Not all of the space available to /dev/sda appears to be used, you can
fix the GPT to use all of the space (an extra <number> blocks) or continue
with the current setting?
Fix/Ignore? F"

Unfortunately, the entire VM froze after selecting the "Fix" option. Subsequently, upon restarting the VM, I have consistently encountered the aforementioned error message.

Has anyone seen this happen before? I am eager to regain normal functionality for my VM as soon as possible.

Thank you.

 

[randomuser1990]

Output from set and ls

 

[randomuser1990]

When looking at the proxmox hosts shell:

fdisk -l
Disk /dev/mapper/pve-vm--100--disk--0: 306 GiB, 328564998144 bytes, 641728512 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 65536 bytes / 65536 bytes
Disklabel type: dos
Disk identifier: 0x00000000

I cant mount it however.

mount /dev/mapper/pve-vm--100--disk--0 /mnt
mount: /mnt: wrong fs type, bad option, bad superblock on /dev/mapper/pve-vm--100--disk--0, missing codepage or helper program, or other error.

 

[fiona]

Hi,
please share the VM configuration with qm config 100. You could use https://www.cgsecurity.org/wiki/TestDisk to try and restore the partition table. Can you see anything in the system logs around the time the issue happened?

 

[randomuser1990]

root@woody:~# qm config 100
boot: order=scsi0;net0;ide2 cores: 8 ide2: local:iso/ubuntu-22.04.1-live-server-amd64.iso,media=cdrom,size=1440306K memory: 32768 meta: creation-qemu=7.1.0,ctime=1675712972 name: teak-server net0: virtio=16:40:ED:1D:D5:BF,bridge=vmbr0,firewall=1 numa: 0 onboot: 1 ostype: l26 scsi0: local-lvm:vm-100-disk-0,iothread=1,size=306G scsihw: virtio-scsi-single smbios1: uuid=186e9491-df6e-4754-8576-5ccd1517fa05 sockets: 1 startup: order=2,up=0 tags: 111 usb0: host=1a86:55d4 vmgenid: 87a299c7-0c10-446a-a73d-127aea41d44c

 

[randomuser1990]

This is around the time I extended the VMs storage.

Jun 07 18:06:14 woody kernel: device-mapper: thin: 253:4: reached low water mark for data device: sending event.
Jun 07 18:06:14 woody kernel: device-mapper: thin: 253:4: switching pool to out-of-data-space (queue IO) mode
Jun 07 18:06:23 woody lvm[604]: WARNING: Thin pool pve-data-tpool data is now 100.00% full.

Jun 08 08:13:31 woody kernel: Buffer I/O error on device dm-8, logical block 14223792
Jun 08 08:17:01 woody CRON[1503212]: pam_unix(cron:session): session opened for user root(uid=0) by (uid=0)
Jun 08 08:17:01 woody CRON[1503213]: (root) CMD (   cd / && run-parts --report /etc/cron.hourly)
Jun 08 08:17:01 woody CRON[1503212]: pam_unix(cron:session): session closed for user root
Jun 08 08:32:07 woody kernel: EXT4-fs warning (device dm-8): ext4_end_bio:344: I/O error 3 writing to inode 10226244 starting block 14223792)
Jun 08 08:32:07 woody kernel: Buffer I/O error on device dm-8, logical block 14223792
Jun 08 08:36:16 woody kernel: EXT4-fs warning (device dm-8): ext4_end_bio:344: I/O error 3 writing to inode 10226244 starting block 14223792)
Jun 08 08:36:16 woody kernel: Buffer I/O error on device dm-8, logical block 14223792
Jun 08 08:36:16 woody kernel: EXT4-fs warning (device dm-8): ext4_end_bio:344: I/O error 3 writing to inode 10226244 starting block 14223793)
Jun 08 08:36:16 woody kernel: Buffer I/O error on device dm-8, logical block 14223793
Jun 08 08:51:07 woody kernel: EXT4-fs warning (device dm-8): ext4_end_bio:344: I/O error 3 writing to inode 10226244 starting block 14223793)
Jun 08 08:51:07 woody kernel: Buffer I/O error on device dm-8, logical block 14223793
Jun 08 08:51:07 woody kernel: EXT4-fs warning (device dm-8): ext4_end_bio:344: I/O error 3 writing to inode 10226244 starting block 14223794)
Jun 08 08:51:07 woody kernel: Buffer I/O error on device dm-8, logical block 14223794

 

[randomuser1990]

Last partition could not be recovered... which makes sense.. it looks... weirdly huge?

Did however not solve the issue :/

 

[fiona]

Jun 07 18:06:14 woody kernel: device-mapper: thin: 253:4: reached low water mark for data device: sending event.
Jun 07 18:06:14 woody kernel: device-mapper: thin: 253:4: switching pool to out-of-data-space (queue IO) mode
Jun 07 18:06:23 woody lvm[604]: WARNING: Thin pool pve-data-tpool data is now 100.00% full.

That means your backing storage, the thin pool associated with local-lvm, got full, so it's no surprise the VM had issues. You need to (re)move some VM images away from the pool or extend it, see the output of lvs for how much is used by each image.

 

[randomuser1990]

Okey, checked now and its sitting at 96% after a bit of cleaning.

So what would be the next step?

 

[randomuser1990]

This is the VM now instead:

 

[randomuser1990]

Testdisk can find 2 partitions. And this is what parted says: